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Questions: Cutting a thin slit


I want to cut very thin slits in clear acrylic (for a motor tachometer encoder). Material thickness is 1.5mm (0.06") and the slit length will be 5mm (0.2") (not critical). I understand the laser cut kerf to be 0.007" to 0.01". If I draw the slit width at 0.01", it would appear from the design guidelines that I would end up with a slit 0.017" to 0.02" wide, ignoring the 1° draft on the sides of the slit. Is this correct?

Can such a thin slit actually be cut and come out as intended? What is the thinnest slit that can be made in this material? Could a slit be cut that is nearly as small as the laser kerf, for instance by drawing the slit to be 0.001" wide?


You are correct. In theory, if you draw a rectangle that is 0.010" wide, it should measure between 0.017" and 0.020" after factoring in the laser’s kerf. However, please note that there are many factors that affect the cutting, so we do not guarantee any particular tolerance.

You should also note that all acrylic/plexiglass materials are infrared transmitting, even opaque colors. For an IR-blocking material, you might consider ABS instead.

- Arthur